전정기능검사에서 정상소견을 보이는 어지러운 환자들의 임상적 특징

정원호,방은국,홍성화,이치규,이현석 대한평형의학회 2002 Research in Vestibular Science Vol.1 No.2

고립성 폐결절의 조직학적 진단에 있어서 경기관지폐생검의 진단적 가치

김치훈,김정주,왕준호,연규민,김형수,리원연,용석중,신계철 건국대학교 의과학연구소 2002 건국의과학학술지 Vol.12 No.-

Transbronchial lung biopsy(TBLB) is a relatively simple and convenient diagnostic tool in solitary pulmonary nodule(SPN) on chest radiograph, which is cannot be diagnosed through routine tests. To investigate the diagnostic value and diagnostic rate of TBLB according to the variable factor, we analyzed 69 patients with radiologically SPN lesion on chest radiograph which was confirmed histologically. A histologic diagnosis of TBLB was made in 47 of 69 patients(68.1%), in which 26 of 37(70.3%) with malignancy and 21 of 32(65.6%) with benign lesion. There were no significant differences in diagnostic yield according to age, sex and location of the lesion. The diagnostic rate tended to increase with the more than 5 pieces to acquired by TBLB. When the size of SPN was less than 3 ㎝, it cannot be diagnosed. In conclusion, TBLB is a diagnostic procedure with good yield and safety, but percutaneous needle aspiration, transbronchial needle aspiration, and bronchial washing fluid cytology may be a complementary procedure to overcome the limitation of TBLB and get higher diagnostic yield for SPN.

악하선 암의 치료성적과 예후인자

임치영(Chi Young Lim),남기현(Kee Hyun Nam),이잔디(Jan Dee Lee),장항석(Hang Seok Chang),정웅윤(Woong Youn Chung),차인호(In Ho Cha),이창걸(Chang Geol Lee),최은창(Eun Chan Choi),박정수(Cheong Soo Park) 대한두경부종양학회 2005 대한두경부 종양학회지 Vol.21 No.2

Purpose: Submandibular gland tumor is rare, less than 6% of head and neck tumor. The purpose of this article is to analysis the clinical experience and treatment outcomes of malignant submandibular gland tumor, suggesting a guideline of management. Methods: We retrospectively evaluated 26 patients who underwent operation for malignant submandibular gland tumor at Severence hospital between 1986 and 2004. Statistical analysis was performed by Kaplan-Meier method, log rank test, Chi-square test, Fisher's exact test using SPSS v12.0 for Windows. Results: They consisted of 18 males and 8 females whose median age was 47 years(range: 20-71). 10 cases of adenocystic carcinoma, 8 cases of carcinoma ex pleomorphic adenoma, 4 cases of mucoepidermoid carcinoma, 1 case each for acinic cell carcinoma, undifferentiated carcinoma, adeno carcinoma, epithelioid hemangioendothelioma. Sialoadenectomy only was performed in 10 cases(36.5%) and sialoadenectomy with neck node dissection was performed in 16 cases(63.5%). Adjuvant radiotherapy was done in 22 cases(84.6%). 10 year disease free survival rate for malignant submandibular gland tumor was 63.1 % and 10 year overall survival rate for malignant submandibular gland tumor was 70.1%. In univariate analysis, prognostic factors affecting recurrence of malignant submandibular gland tumor was initially papable lateral neck node in physical examination and metastasis of lateral neck node in pathologic confirmation. The prognostic factors affecting survival of malignant submandibular gland tumor was tumor size, TNM stage, recurrence and type of recurrence. Conclusion: In this study, prognostic factors affecting recurrence of malignant submandibular gland tumor was initially papable lateral neck node in physical examination and metastasis of lateral neck node in pathologic confirmation. The prognostic factors affecting survival of malignant submandibular gland tumor was tumor size, TNM stage, recurrence and type of recurrence. To prevent recurrence and to improve survival, early diagnosis and aggressive surgery must be considered.

공동주택 연료전지 열교환기의 안전설계 및 특성 분석

RIGUANG CHI, 송의혁, 최재혁, 이동훈, 이석호 충북대학교 산업과학기술연구소 2019 산업과학기술연구 논문집 Vol.33 No.2

본문참조

1%Cr-Mo-V 강 회전자축의 크리이프 특성과 수명예측에 관한 연구

이치우,장윤석,정순호,조판근 慶南大學校 附設 工業技術硏究所 1986 硏究論文集 Vol.4 No.-

본 연구는 1%Cr-Mo-V강 회전자축의 보다 개선된 크리이프특성을 위한 최적열 처리 조건의 선정과 크리이프 수명을 예측하기 위하여 행해졌다. 실험결과 970℃∼980℃ 퀜칭/660℃∼680℃ 템퍼링의 조합에서 최적크리이프 특성치가 나타났다. 또한 Larson-Miller법 및 Curvelinear Regression법에 의해 1%Cr-Mo-V강 회전자축의 주파단곡선을 구하였다. 회전자축이 530℃에서 연속 작동되며 순수크리이프 변형만을 고려할 때 회전자축의 최고응력 집중부에서의 예상크리프수명은 21.9×105hrs이었다. This study was carried out to find out optimum heat treatment conditions for improved creep properties and to estimate creep life of 1% Cr-Mo-V-steel rotor shaft. The effect of heat treatment on the creep properties of 1% Cr-Mo-V-steel rotor shaft was investigated under the conditions of various heat treatment temperatures. Experimental result shows that the best combination of quenching and tempering temperatures for good creep properties is 970℃-980℃ quenching 660℃-680℃ tempering sequence. A master curve for 1% Cr-Mo-V-steel rotor shaft was obtained by Larson-Miller parameter and curvelinear regression method. Life prediction at the maximum stress concentration points in the rotor was computed about 21.9×10??hours, if the rotor shaft would be continuously operated at 530℃ and be influenced by the effect of creep strain only.

두 가족의 가족성 모야모야병 환자 4례

구자성,노재규,박성호,이한보,이용석,윤창호,송치성,송재우 대한신경과학회 1998 대한신경과학회지 Vol.16 No.4

로타바이러스 원내 감염과 지역사회 획득 감염의 비교 연구

유재성,진현주,강호석,오지은 고신대학교 의과대학 2010 고신대학교 의과대학 학술지 Vol.25 No.2

Purpose: This study was performed to investigate the epidemiologic and clinical characteristics of rotaviral infection, the most common nosocomial gastroenteritis. Method: We retrospectively reviewed the records of 983 patients who were diagnosed as rotavirus gastroenteritis from January 2006 to March 2010. We divided them into two groups: group A for community-acquired rotavirus infection (N=810), group B for nosocomial infection (N=173). We investigated the characteristics of both groups. Results: The percentage of nosocomial infection among rotavirus gastroenteritis was 18% in our study. Rotaviral infection in both groups was more common in winter. The average age (±SD) of group A and B was 25.8±23.3 and 17.8±15.7 months old, respectively. The average hospital days (±SD) were 4.3±2.0 days for group A and 9.0±3.5 days for group B. Nosocomial infection symptoms of group B started at 4.6±1.7 hospital days on average. Fever, vomiting, abdominal pain, convulsion, elevation of serum CRP (C-reactive protein) or AST (Aspartate aminotransferase) were observed more common in group A than B. Conclusion: The nosocomial rotavirus infection rate did not decrease as we expected in spite of our effort of strict hygiene control. Nosocomial infection showed more favorable prognosis than community-acquired infection but demanded longer days of hospitalization and more cost.

페놀분해 효모 Candida tropicalis PW-51의 분리 및 분해특성

김성빈,김치경,김희식,이창호,신기선,권시석,윤병대,오희목 한국미생물생명공학회 ( 구 한국산업미생물학회 ) 1996 한국미생물·생명공학회지 Vol.24 No.6

본 연구는 페놀과 포름알데히드를 포함하는 페놀계수지 산업폐수의 생물학적 처리에 이용할 목적으로 포름알데히드의 존재하에서 페놀분해능이 우수한 효모를 sludge로부터 분리하여, 형태적 및 생리 생화학적 특징을 조사하여 Candida tropicalis PW-51로 동정하였다. 회분식 배양에서 C. tropicalis PW-51의 페놀 분해한계는 2,000 mg/ℓ이며, 58시간내에 완전히 분해하였다. C. tropicalis PW-51은 초기접종량이 9×10 exp (6) cells/㎖, 배양온도는 30℃, pH는 7.0에서 페놀 분해효율이 높았으며, 500~2,000 mg/ℓ의 페놀농도에서 조사된 페놀에 대한 평균 분해율은 페놀 1,000 mg/ℓ에서 45.5 mg/ℓ/h 가장 높았다. C. tropicalis PW-51의 페놀분해시 catechol 1,2-dioxygenase의 활성이 크게증가하므로 ortho-path-way에 의해 페놀을 분해하는 것으로 판단되었다. 따라서, C. tropicalis PW-51는 페놀계 수지 산업폐수의 생물학적 처리에 효과적으로 이용될 수 있는 균주로 사료된다. For the biological treatment of phenolic resin wastewater containing phenol and formaldehyde, a phenol-degrading yeast was isolated from the papermill sludge, and then identified as Candida tropicalis PW-51 according to morphological, physiological and biochemical properties. The strain was able to degrade high phenol concentrations up to 2,000 mg/ℓ within 58 hours in batch cultures. Phenol-degrading efficiency by the strain was maximum at the culture conditions of a final concentration of 9×10 exp (6) cells/㎖ 30℃ and pH 7.0. The mean degradation rate of phenol was highest at 45.5 mg/ℓ/h in 1,000 mg/ℓ phenol from 500 mg/ℓ to 2,000 mg/ℓ phenol. Because the enzyme activity of catechol 1,2-dioxygenase increased in the course of degradation of phenol, it seems that this strain degrades phenol via the ortho-cleavage of benzene ring. The isolate C. tropicalis PW-51 could be effectively used for the biological treatment of phenolic resin wastewater.

공정변수의 변동을 고려한 호감도 함수를 통한 다중반응표면 최적화

권준범,이종석,이상호,전치혁,김광재 한국경영과학회 2005 한국경영과학회지 Vol.30 No.1

A desirability function approach to a multiresponse problem is proposed considering process parameter fluctuation which may amplify the variance of response. It is called POE(propagation of error), which is defined as the standard deviation of the transmitted variability in the response as a function of process parameters. In order to obtain more robust process parameter setting, a new desirability function is proposed by considering POE as well as distance-to-target of response and variance. The proposed method is illustrated using a rubber product case in Ribeiro et al. (2000).

원전 저압케이블 열화도 평가를 위한 초음파 음속계측에 관한 연구

김경조,강석철,구철수,김진호,박재석,주금종,박치승 한국비파괴검사학회 2004 한국비파괴검사학회지 Vol.24 No.4

원자력발전소에는 여러 종류의 케이블이 전력공급, 감시 및 제어신호의 전달을 위해 열악한 환경하에서 이용되고 있다. 발전소의 안전한 운전을 위해서 이 케이블이 어느 정도 열화 되었는지 확인할 필요가 있다. 특히, 원자력발전소의 수명 연장과 더불어 저압 케이블을 장기간 사용함에 따라서 저압케이블의 열화를 평가하기 위한 방법이 필요하게 되었다. 저압케이블의 열화를 측정하는 파라미터로는 주변 온도, 절연재질의 경도, 파단시 연신률(EAB, Elongation At Breaking Point)등이 있다. 그러나, 온도나 경도를 계측하는 검사는 정량적인 판단기준의 설정이 곤란하고 진단의 정밀도가 낮으며, 부분적으로 샘플링하는 방법은 샘플링되는 케이블에 연결된 부하를 정전시켜야 하고 장소와 시간적인 제약이 있으며, 전기적 측정법은 노화 초기부터 중기까지의 열화정도를 확인하기 어렵다. 본 연구에서는 재료의 열화에 따라서 초음파의 음속이 변화한다는 이론적인 배경 [1,2]를 바탕으로 저압 케이블 재료의 열화에 따른 초음파의 음속을 측정하였다. 이를 위해, 원자력발전소에서 사용되는 저압케이블을 가속 열화시켰으며, 저압케이블의 피복재에서 초음파의 음속을 측정할 수 있는 장비를 개발하여, 초음파의 음속측정 후 인장시험을 통해 파단시 연신률을 측정하였다. 파단시 연신률이 증가함에 따라서 음속이 선형적으로 감소 하였으며, 초음파의 음속은 열화의 정량적 평가 파라미터로서의 사용 가능성을 확인할 수 있었다. Several kinds of low voltage cables have been used in nuclear power plants for the supply of electric power, supervision, and the propagation of control signals. These low voltage cables must be inspected for safe and stable operation of nuclear power plants. In particular, the degradation diagnosis to estimate the integrity of low voltage cables have recently been emphasized according to the long use of nuclear power plants. In order to evaluate their degradation, the surrounding temperature or hardness is not useful because of the absence of quantitative criteria; the inspection of a sample requires turning off of the power plant power; and, the electrical inspection method is not sufficiently sensitive from the initial through the middle stage of degradation. In this research, based on the theory that the ultrasonic velocity changes with relation to the degradation of the material, we measured the ultrasonic velocity as low voltage cables were degraded. To this end, an ultrasonic degradation diagnosis device was developed and used to measure the ultrasonic velocity with the clothing on the cable, and it was confirmed that the ultrasonic velocity changes according to the degradation of low voltage cables. The low voltage cables used in nuclear power plants were degraded at an accelerated rate, and EAB was measure in a tensile test conducted after the measurement of ultrasonic velocity. With the increasing degradation degree, the ultrasonic velocity decreased, whose potential as a useful parameter for the quantitative degradation evaluation was thus confirmed.